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991.
992.
The authors describe a patient with osteosarcoma in whom a brain abscess developed after autologous peripheral stem cell transplantation. Serologic markers of fungal infection were negative, but fungal DNA was detected in the cerebrospinal fluid (CSF) by panfungal polymerase chain reaction (PCR) assay using primers derived from fungal 18S ribosomal RNA (rRNA) genes. The sequence of PCR products on the panfungal assay was identical to the 18S rRNA genes of Aspergillus species. The combination of sequence analysis and panfungal PCR assay could be useful in the diagnosis of cerebral aspergillosis.  相似文献   
993.
SHP-1 is an important negative regulator involved in signaling through receptors for cytokine/growth factors, and differential patterns of SHP-1 expression in several types of B-cell lymphomas closely resemble the patterns seen in their normal B cell counterparts. In an effort to elucidate the origin of primary central nervous system lymphomas (PCNSL), the present study assessed 32 cases of PCNSL. Tumors were subclassified according to WHO classification and were evaluated by immunohistochemistry for expression of antigens associated with germinal center (GC) (CD10, Bcl-6) and non-GC stages (SHP-1, CD138). Twenty-nine cases showed diffuse large-cell centroblastic morphology, whereas three cases showed diffuse large-cell immunoblastic morphology. The immunophenotypes of PCNSL were as follows: SHP-1+/Bcl-6-/CD10-/CD138- (12 of 32 cases); SHP-1+/Bcl-6+/CD10-/CD138- (15 of 32 cases); SHP-1+/Bcl-6+/CD10+/CD138- (two of 32 cases); SHP-1+/Bcl-6-/CD10+/CD138- (one of 32 cases); and SHP-1-/Bcl-6-/CD10-/CD138- (two of 32 cases). These results indicate that PCNSL might be distinct lymphomas that originate from a late germinal center to an early postgerminal center.  相似文献   
994.
Annexin (Anx) V is pivotal in the maintenance of pregnancy by preventing the activation of blood coagulation. The homology of the amino acid sequence between Anx IV and Anx V is highest in Anx family proteins. However, little is known about the roles of Anx IV in pregnancy. The aim of this study is to clarify the roles of circulating Anx IV and Anx V in normal pregnancy. Subjects were non-pregnant women (n = 50), 120 pregnant women, and maternal subjects just after delivery (n = 53) or postpartum (n = 67). Anx IV in the plasma of non-pregnant women was at a concentration 20 times that of Anx V. The plasma levels of Anx IV suddenly increase after delivery, but Anx V levels remain low during this period. Anx IV and Anx V exert similar levels of anticoagulant activity. Anx IV protein was expressed on the basal surface of syncytiotrophoblasts; Anx V protein, on the apical surface of syncytiotrophoblasts. These results suggest that Anx IV enters the maternal bloodstream just after delivery and might play a role in preventing disseminated intravascular coagulopathy, and that Anx V helps to prevent clotting in the placenta during pregnancy.  相似文献   
995.
The report of Fuchs et al. in 1999 on the protective effects of dietary fiber (DF) against colon carcinogenesis has led many researchers to question the benefits of DF. We analyzed the relationship between dietary intake and mortality from colon cancer in Japan cross-sectionally. Dietary data were taken from the National Nutrition Survey. The standardized mortality ratio (SMR) was calculated using data from "Vital Statistics" and "the Population Census in Japan." Multiple regression analysis (stepwise variable selection method) was performed with the SMR of colon cancer as the objective variable and intake of DF, nutrients, and food groups in 1966 as the explanatory variables. The beta regression coefficient was significantly positive for intakes of fat, protein, and vitamin C and significantly negative for intakes of calcium and vitamin A to the SMR of colon cancer. However, no significant correlation was observed for DF or for any of the various food groups analyzed. In conclusion, our data do not demonstrate any protective effect of DF on colon cancer in subjects with a low fat intake (Japanese subjects), which supports Fuchs' findings in subjects with high fat intake (U.S. subjects).  相似文献   
996.
Now that treatment of H. pylori associated disease is becoming common in Japan, drug resistant--H. pylori has emerged as a problem to be solved. There is no standard method of H. pylori drug susceptibility test in Japan yet. There are several methods available: Disk test, E-test, microplate method and agar plate dilution method. The E-test is being the standard method in European countries and USA. However the microplate method has been reported as a same accuracy as the agar dilution method, and thought as being a new standard method in Japan. In 2000, The Japanese Society of Chemotherapy proposed that drug susceptibility test be standardized and listed the break point of MIC of amoxicillin(AMPC) and clarithromycin(CAM).  相似文献   
997.
Our purpose was to compare the characteristics of J-shaped detachable platinum coils with those of spiral coils in in-vitro vascular models. J-shaped coils consist of distal semicircular and proximal straight segments, the latter extending for most of the length of the coil. Spiral coils have a helical shape memory and are thus limited in expansion. In in-vitro silicone vascular models simulating intracranial aneurysms and dural arteriovenous fistulae, we compared J-shaped and spiral coils with regard to ease of delivery, anchoring and folding patterns, and stability in various types of vascular lumen. Delivery and retrieval were comparable. In large and irregular aneurysms and venous sinuses, J-shaped coils could form a more complex basket which conformed to the shape of the vascular cavity. The J-shaped coil was always in contact with the vessel wall. In wide-necked aneurysms, coil protrusion was more frequent with J-shaped coils, while spiral coils tended to stay compact and circular. Arteries were occluded in a shorter segment with spiral coils. J-shaped coils were safe and superior for large and irregular aneurysms or sinuses. Spiral coils were preferable for spherical aneurysms and segmental occlusion of arteries.  相似文献   
998.
MRI of large pituitary adenomas has revealed that a posterior pituitary bright spot (PPBS), comprising ADH-containing neurosecretory granules, is commonly ectopic before surgery and attached to the tip of the pituitary stalk late after surgery. Although the PPBS indicates functional integrity of the posterior lobe, transient diabetes insipidus (DI), caused by deficiency of ADH, is frequent early after surgery. We attempted to clarify how the shape, signal intensity and site of the PPBS before surgery are related to transient DI in the early postoperative period. We carried out MRI on 15 patients with a large adenoma and an ectopic PPBS before surgery and then within 1 week (early), 1–2 months (intermediate) and 6 or more months (late) after the operation. There were nine who had transient DI, which subsided by the intermediate study; none had permanent DI. Regardless of transient DI, the PPBS was visible, and its signal intensity was similar, on all postoperative studies. Although 11 did not change in shape, four showed a remarkable change from a flat shape before surgery to a rounded one postoperatively. On the intermediate MRI, the PPBS had descended to the level of the diaphragma as mass effect disappeared.  相似文献   
999.
Arylalkylamine N-acetyltransferase (AA-NAT) is a rate-limiting enzyme in melatonin hormone synthesis and participates in daily oscillations of the melatonin level. We studied the association between the AA-NAT gene and delayed sleep phase syndrome (DSPS). Results indicate that there is a significant difference in allele positivity at the single nucleotide polymorphism involved in an amino acid substitution from alanine to threonine at position 129 between patients with DSPS and healthy controls. The frequency of the 129 threonine allele is significantly higher in the patients than in the controls (P=0.0029). The data suggest that AA-NAT could be a susceptibility gene for DSPS. Electronic Publication  相似文献   
1000.
The effect of toluene inhalation on oxidative damage in rat organs was examined. Male Wistar rats was inhaled toluene (1500 ppm for 4 h a day) for 7 days. Quantitatively and immunohistochemically, oxidative DNA damage, lipid peroxide (LPO) and superoxide dismutase (SOD) were examined. As a marker of the oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) immunoreactivity increased in the lung, liver and kidney. The amount of 8-OH-dG also increased in liver and kidney significantly. In the testis, the amount of 8-H-dG did not increase, however 8-OH-dG immunoreactivity enhanced in the spermatogonia. SOD immunoreactivity increased in the lung, liver and kidney. However, 4-hydroxy-nonenal immunoreactivity and the amount of LPO did not change in each organ. Thus, oxidative damage by toluene is mainly DNA damage, especially, the oxidative DNA damage observed in the lung, liver and kidney for the increase of the immunoreactivity and amount of 8-OH-dG.  相似文献   
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